A woman helps adjust a mask for her friend outside an amusement park on a hazy day in Beijing Saturday, Jan. 12, 2013. Air pollution levels in China's notoriously dirty capital were at dangerous levels Saturday, with cloudy skies blocking out visibility and warnings issued for people to remain indoors.

Photo: Alexander F. Yuan, Associated Press

A woman helps adjust a mask for her friend outside an amusement...

A woman helps adjust a mask for her friend outside an amusement... Photo-4022776.55058 - SFGate

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An ice swimmer wears a green cap with two table tennis balls at the Oranke sea in Berlin, on January 12, 2013.Spectators and ice bathers from 17 clubs enjoyed the cold water.

Photo: Britta Pedersen, AFP/Getty Images

An ice swimmer wears a green cap with two table tennis balls at the...

Bikers take a bath in a self-constructed bath tube in front of the Augustusburg Castle in Augustusburg, eastern Germany, on January 12, 2013. Up to 1,500 bikers from whole Europe attend the event, the tradition goes back to 1971.

Photo: Arno Burgi, AFP/Getty Images

Bikers take a bath in a self-constructed bath tube in front of the...

Bikers take a bath in a self-constructed bath tube in front of the... Photo-4022779.55058 - SFGate

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A man wearing a headdress and another wearing a ski mask sit on a windowsill on the site of an old Indian museum, in Rio de Janeiro, Brazil, Saturday, Jan. 12, 2013. Police in riot gear on Saturday surrounded the site in preparation for the eviction of an indigenous settlement of men and women living on the grounds of the old museum. The museum is located next to the Maracana stadium, which is being refurbished to host the opening and closing ceremonies of the 2016 Olympics and the final match of the 2014 World Cup. Authorities say the compound must go as the area around the stadium is also being refurbished, expected to be transformed into a shopping and sports entertainment hub.

Photo: Felipe Dana, Associated Press

A man wearing a headdress and another wearing a ski mask sit on a...

A man wearing a headdress and another wearing a ski mask sit on a... Photo-4022787.55058 - SFGate

Chess players Magnus Carlsen (L) from Norway and Fabiano Caruana (R) from Italy compete during a game of chess at the Tata Steel Chess Tournament in Wijk aan Zee, the Netherlands, on January 12, 2013, as Chinese player Hao Wang looks on in the background.

A man sweeps an exposed tiled area of the earthquake-damaged Santa Ana Catholic church, where he now lives, in Port-au-Prince, Haiti, Saturday, Jan. 12, 2013. Haitians recalled Saturday the tens of thousands of people who lost their lives in the devastating earthquake three years ago. Most of the rubble created by the quake has since been carted away but more than 350,000 people still live in displacement camps.

Photo: Dieu Nalio Chery, Associated Press

A man sweeps an exposed tiled area of the earthquake-damaged Santa...

A man sweeps an exposed tiled area of the earthquake-damaged Santa... Photo-4022791.55058 - SFGate

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Indian women perform rituals on the beach at Gangasagar, India, Saturday, Jan. 12, 2013. The annual holy dip at Gangasagar, the confluence of Ganges River and Bay of Bengal, some 140 kilometers (87 miles) south of Kolkata, on the occasion of Makar Sankranti, is scheduled on Jan. 14.

Photo: Bikas Das, Associated Press

Indian women perform rituals on the beach at Gangasagar, India,...

Indian women perform rituals on the beach at Gangasagar, India,... Photo-4022794.55058 - SFGate